The long-term goals of this research project are to dissect the molecular and cellular biology of olfactory memory formation in Drosophila. A recent screen for new memory mutants with putative functions in the mushroom body neurons has uncovered several putative mutants, but one with a strong effect on performance immediately after training. Experiments are proposed to completely characterize the nature of the disrupted expression in different alleles of this gene, to reveal the spatial expression pattern of the gene within the olfactory nervous system, and to probe behaviorally whether the various alleles disrupt acquisition or memory stability. Genetic tests will reveal whether the mutant disrupts a molecule that is a member of well characterized signaling systems important for memory formation or whether this new gene represents the prototypic member of a parallel signaling system. Newly developed techniques to control transgene expression in time and in space will be used to address the issue of when and where the gene product is required for normal memory formation. Overall, the experiments will contribute to our understanding of the molecular biology of learning, an important process disrupted in many different diseases of the nervous system including Alzheimer's disease, schizophrenia, autism, and learning disabilities.